JP2000175188A - Information recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information recorder that can flexibly cope with recording of information depending on contents thereof. SOLUTION: A source discrimination device 14 discriminates a received source, A security level discrimination device 16 decides a security level depending on a kind of an input signal. A 1st encoder 18 encodes the input signal at a recording transfer rate corresponding to the discrimination result by the security level discrimination device 16 or does not execute coding depending on the security level. A 2nd encoder 20 adds a required signal to an encoded signal in matching with a format of a recording medium 26. A recording head drive circuit 22 changes a signal after encoding into an optical signal or a magnetic signal and a recording head 24 records the signal to the recording medium 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording apparatus for recording various kinds of information such as images, sounds, programs and the like on a recording medium such as a DVD or DVC, and more particularly to an improvement of an information recording technique suitable for copyright protection. Things.

[0002]

2. Description of the Related Art In recent years, large-capacity digital information signal recording / reproducing systems represented by DVDs and DVCs have been commercialized. These digital systems are capable of recording and reproducing high-quality sound and high-quality video for a long time as compared with conventional analog systems. Information such as video and music is represented as a digital signal. For this reason, there is a transmission feature that the information is not degraded when the signal is copied (copied) as compared with the case where the signal is represented by an analog signal. For these reasons, it has become a serious problem in copyright protection, and digital copying in which digital signals are directly copied in the form of digital signals is prohibited or certain restrictions are imposed.

In recent years, digital broadcasting such as CS and D
Like VD-MOVIE, digitally recorded contents tend to increase, and this tendency is expected to become even more pronounced in the future. In the future, it is expected that higher-quality digital contents such as digital terrestrial broadcasting and digital HDTV will appear. From such a viewpoint, it is desired to solve the copyright problem of the digital copy.

[0004] As proposed from such a point,
There is an SCMS (Serial Copy Management System) adopted in the MD signal recording system. In the SCMS, a part of the digital signal includes a protection code (protection code) regarding whether or not copying is possible. When the MD device copies a signal, the system refers to the protection code to prevent more than one digital copy. Specifically, a protect code is written in data in the TOC (Total of Content) area of the MD. If the protection code is "no protection", the MD signal can be copied. When the copy is performed, a protection code “protected” is written in the TOC area of the copy destination MD. If the protection code is "protected", it cannot be copied thereafter. In this way, more than one digital copy is prevented.

[0005]

However, the above prior arts have the following disadvantages. (1) In a method such as the above-described SCMS, only three types, that is, copying is impossible, copying is possible only once, and copying is unlimited, are set, and the system flexibly responds to diversified digital contents and user needs. Is not always satisfactory. (2) In the case where information recorded on the MD is directly read out as a recording signal and is recorded on another medium, the protection code is copied irrespective of the contents of the protection code. Will be. For this reason, copying can be performed any number of times, and illegal copying in terms of copyright cannot be prevented.

The present invention focuses on the above points, and an object of the present invention is to provide an information recording technique which can flexibly cope with diversifying digital content security levels and is effective for copyright protection. It is assumed that.

[0007]

In order to achieve the above object, the present invention provides an information recording apparatus which encodes an input signal with a variable transfer rate and records it on a recording medium, according to a source of the input signal. Security level determining means for determining the security level; at a transfer rate corresponding to the security level determined thereby,
Encoding means for encoding the input signal. According to one of the main modes, the security level determining means includes: a source determining means for determining a source of the input signal;
Security level determining means for determining a security level.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In FIG. 1, a digital input signal 10 and an analog input signal 12 are shown.
Are input to the source determination unit 14. The output side of the source determiner 14 is connected to the security level determiner 16. The output side of the security level determiner 16 is connected to the second encoder 20 via the first encoder 18.
It is connected to the. The output side of the second encoder 20 is connected to a recording head 24 via a recording head drive circuit 22.
It is connected to the. A signal is recorded on the recording medium 26 by the recording head 24.

Next, the overall operation will be described. A signal to be recorded is input to a source determining unit 14. The source determiner 14 determines the source of the input signal. That is, first, it is determined whether the input signal is an analog signal or a digital signal. Further, when the input signal is a digital signal, it is determined what kind of digital signal the signal is. The types of digital signals include, for example, DV signals from digital video cameras, CS digital broadcast signals, and MPEG2 signals from DVD videos. In the future, BS and terrestrial digital broadcast signals are also conceivable. Which of these types is determined from the code or signal indicating the source.

The security level judging unit 16 determines the copyright security level according to the type of the input signal judged by the source judging unit 14. The signal transfer rate when recording the input signal on the recording medium is determined by the security level. The quality of a signal to be recorded greatly depends on the transfer rate at the time of recording. If the recording transfer rate is the same as at the time of input, the signal quality does not decrease and the quality of the original signal and the copied signal are equal. However, if the recording transfer rate is lower than at the time of input, the signal quality deteriorates, and the lower the transfer rate, the greater the quality difference from the original signal.

Next, the first encoder 18 encodes the signal at the transfer rate determined by the security level determiner 16. In the second encoder 20, an address, an error correction code, and the like are added to the signal encoded by the first encoder 18 according to the format of the medium to be recorded. In the recording head drive circuit 22, the encoded signal is converted into an optical signal or a magnetic signal and supplied to the recording head 24. In the recording head 24, data is recorded on the recording medium 26 based on the input signal.

Next, the relationship between the input signal judgment by the source judgment unit 14, the judgment by the security level judgment unit 16, and the transfer rate of the encoding by the first encoder 18 will be specifically described with reference to FIG. This figure 2
In the example, the input signal is first discriminated into an analog signal and a digital signal. And for analog signals,
The security level is determined to be “0”. In this case, the moving image signal or the audio signal, which is the input signal, is encoded at a transfer rate of a value set as a default in advance.

On the other hand, in the case of a digital signal, the security level is further divided into a plurality depending on, for example, the contents of the information and the new and old exhibition periods. In the illustrated example, the digital signal is divided into four levels. First, in the case of the digital signal A having the security level 1, the moving image signal or the audio signal is encoded at the same transfer rate as the original signal. In this case, the quality of the signal recorded on the recording medium 26 is the same as the quality of the original signal. For example, a copyright-free video taken by a home digital video camera or the like corresponds to the security level 1.

Next, in the case of the digital signal B having the security level 2, the moving image signal or the audio signal is encoded and recorded at a transfer rate of two thirds of the transfer rate of the original signal. In this case, the quality of the signal recorded on the recording medium 26 is slightly deteriorated from the quality of the original signal. This level 2 is applied when the content provider accepts a certain amount of copying but does not want to copy the original quality.

Next, in the case of the digital signal C having the security level 3, the moving image signal or the audio signal is encoded and recorded at a transfer rate that is half the transfer rate of the original signal. In this case, the quality of the signal recorded on the recording medium 26 is further deteriorated as compared with the quality of the original signal, and is lower than the digital signal B of security level 2. This case is also applied to a case where the content provider accepts a certain amount of copying but does not want to copy the original quality.

Next, in the case of the digital signal D of security level 4, since the recording itself is disabled,
No encoding is performed. This applies when the content provider does not permit copying. This prevents unauthorized copying.

Next, another embodiment will be described with reference to FIG. In this embodiment, for example, the source determination unit 3
When it is determined that the signal is an analog signal at 0, the input signal is supplied to the encoder 18 without performing the determination by the security level determiner 32. As shown in FIG. 2, in the case of an analog signal, the security level is “0” and the transfer rate is a default value. Therefore, there is no need to determine the security level.

[0018]

As described above, according to the present invention,
The following effects can be obtained. Since the security level of the target content is determined at the time of encoding the signal, it is possible to solve the copyright problem while enabling copying. Further, by not performing encoding depending on the security level, illegal copying can be prevented. Since the copy transfer rate is changed in accordance with the security level, it is possible to construct a recording system that can flexibly respond to the needs of the content provider and the user.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a diagram illustrating a relationship among a source, a security level, and a recording transfer rate.

FIG. 3 is a block diagram showing a configuration of another embodiment of the present invention.

[Explanation of symbols]

 14, 30 source determiner 16, 32 security level determiner 18 first encoder 20 second encoder 22 printhead drive circuit 24 printhead 26 print medium

Claims (2)

[Claims] 1. An information recording apparatus that encodes an input signal at a variable transfer rate and records the encoded signal on a recording medium, comprising: a security level determining unit that determines a security level according to a source of the input signal; Encoding means for encoding the input signal at a transfer rate corresponding to the security level set. 2. The security level determining means includes: source determining means for determining a source of the input signal; and security level determining means for determining a security level according to a result of the determination. Item 2. The information recording device according to Item 1.